> ## Content Index
> Fetch the complete content index at: https://www.fdaweb.com/llms.txt
> Use this file to discover other available public pages before exploring further.

# Janssen, Novavax Report Positive Covid Vaccine Data
- URL: https://www.fdaweb.com/janssen-novavax-report-positive-covid-vaccine-data/
- Published: 2021-01-29T12:00:00.000Z
- Updated: 2026-09-14T16:44:44.000Z
- Author: David McFarland
- Tags: Biologics, #legacy-id-D5148555

Janssen and Novavax have both reported positive data from Phase 3 clinical trials involving each of their investigational Covid-19 vaccines. [Janssen says](https://www.jnj.com/johnson-johnson-announces-single-shot-janssen-covid-19-vaccine-candidate-met-primary-endpoints-in-interim-analysis-of-its-phase-3-ensemble-trial?ref=fdaweb.com) its vaccine was 72% effective in the U.S. and 66% effective overall at preventing moderate to severe Covid-19\. The vaccine’s Phase 3 data also show that it was 85% effective overall in preventing severe disease and demonstrated 100% protection against Covid-19 related hospitalization and death as of day 28 post-vaccination. The company plans to file for FDA Emergency Use Authorization (EUA) in early February and expects to have product available to ship immediately after an EUA is granted.

Meanwhile, Novavax says a UK Phase 3 trial has shown vaccine efficacy of 89.3%. “The study assessed efficacy during a period with high transmission and with a new UK variant strain of the virus emerging and circulating widely,” [it says](https://ir.novavax.com/news-releases/news-release-details/novavax-covid-19-vaccine-demonstrates-893-efficacy-uk-phase-3?ref=fdaweb.com). The company’s PREVENT-19 U.S. and Mexico Phase 3 clinical trial has randomized over 16,000 participants and should reach its enrollment goal of 30,000 by mid-February. The trial is being conducted with support from the U.S. government partnership formerly known as Operation Warp Speed.